Magnetic resonance imaging (MRI) is a relatively slow imaging technique because of the nature of its acquisition, which relies on exciting the spins of atoms and recording their relaxation times within a spatial encoding scheme. Nonetheless, MRI is one of the most compelling imaging modalities that has enabled advanced in-vivo analysis of brain activity and neuronal microstructure using techniques such as functional MRI and diffusion-weighted (DW)-MRI. These advanced imaging techniques require relatively long acquisitions that are, consequently, very susceptible to the subject's motion. When possible, subjects and patients are asked to stay still during MRI scans, but motion is inevitable.
Extensive research has been carried out on motion-robust sequences and motion correction techniques in MRI. However, the use of motion compensation techniques is limited by the type and amount of motion that can be compensated for, the dependency on the scanner platform and the need for pulse sequence modifications, and/or difficult setup. Accordingly, current MRI practice is still based on prevention of motion. In newborns, young children, and patients with limited cooperation, this commonly requires full sedation or general anesthesia, which is time consuming, costly, and is associated with significant risks.